Sharp Aquos LC-80LE642U, Service Manual

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LC-80LE642U
6 – 14
No video (5)
No video at UHF/VHF broadcast signal reception No video at digital broadcast signal reception
Is the specified TV signal selected on the input select menu screen?
Are there the IF signal at input pins(AT32/AU32)(TUN_IFN/P)
of IC3301(CPU)? Are there the IF signal at input pins(AT32/AU32)(TUN_IFN/P) of
IC3301(CPU)?
Is there IF-AGC signal at input pin(12) of TU1104?
YES
NO
YES
NO
Check the IF signal line between IC3301 and
TU1104, and their peripheral circuits. Check the IF signal line between IC3301 and
TU1104, and their peripheral circuits.
Check the Tuner I2C lines.
TU1104:pin(5)(TUN_SCL), pin(4)(TUN_SDA)
IC3301:pin(V35), pin(V34)
Check the IF-AGC line between pin(U35) of IC3301
and pin(12) of TU1104.
Check the Tuner I2C lines.
TU1104:pin(5)(TUN_SCL), pin(4)(TUN_SDA)
IC3301:pin(V35), pin(V34)
Is the T-CON PWB connected?
VBO_LOCKN (40pin) of SC3801 become Low if there is no problem in the connec-
tion. NO Check the T-CON PWB and harness.
Check IC3301 and SC3801 and their peripheral cir-
cuits in Main PWB.
YES
Are the V-By-One HS signal input to the pin of SC3801?
VBO/- (36/37pin), VBO/- (32/33pin),
VBO/- (28/29pin), VBO/- (24/25pin). NO Check IC3301 and its peripheral circuits.
(IC3501/IC3502/IC3503/IC3504, etc.)
YES
Check the panel module and harness.